Gas diffusion barrier characteristics of Al2O3/alucone films formed using trimethylaluminum, water and ethylene glycol for organic light emitting diode encapsulation

Abstract

Al2O3/alucone barrier films were deposited by using atomic layer deposition and molecular layer deposition at 85 °C. Fourier transform infrared spectroscopy spectra reveal that the chemical bonding states, such as those of O–H, C–H, and C–O groups, changed rapidly in alucone films because the water vapor may absorb and/or react with the alucone film. The water vapor transmission rate (WVTR) measured by the calcium test of alucone film was similar to that of polyethylene naphthalate. However, the hybrid Al2O3/alucone films (2.08×10−2g/m2day) show better WVTR properties than that of Al2O3 single layer (3.73×10−2g/m2day) or that of alucone (1.14g/m2day). Hybrid layers can drastically improve the water vapor diffusion barrier property because the alucone layer may increase the water vapor diffusion path in the film and decrease the diffusion speed by trapping water vapor chemically. These promising hybrid layers can create a synergy effect to improve not only the WVTR property but also the flexible property.